Accuracy and Precision Measurements are qualitative or quantitative
![Accuracy and Precision • Measurements are qualitative or quantitative. – Qualitative measurements give results Accuracy and Precision • Measurements are qualitative or quantitative. – Qualitative measurements give results](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-1.jpg)
![Accuracy and Precision • Measurements work best when they are accurate and precise – Accuracy and Precision • Measurements work best when they are accurate and precise –](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-2.jpg)
![Accuracy and Precision Accuracy and Precision](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-3.jpg)
![Accuracy and Precision Accuracy and Precision](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-4.jpg)
![Accuracy and Precision • In this picture, all of the darts land on the Accuracy and Precision • In this picture, all of the darts land on the](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-5.jpg)
![Accuracy and Precision • Here the darts are not close to each other, but Accuracy and Precision • Here the darts are not close to each other, but](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-6.jpg)
![Accuracy and Precision • Sometimes there is a difference between the accepted value and Accuracy and Precision • Sometimes there is a difference between the accepted value and](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-7.jpg)
![Accuracy and Precision • Often it is useful to calculate relative error, or percent Accuracy and Precision • Often it is useful to calculate relative error, or percent](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-8.jpg)
- Slides: 8
![Accuracy and Precision Measurements are qualitative or quantitative Qualitative measurements give results Accuracy and Precision • Measurements are qualitative or quantitative. – Qualitative measurements give results](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-1.jpg)
Accuracy and Precision • Measurements are qualitative or quantitative. – Qualitative measurements give results that are descriptive and non-numerical. • Example: – Quantitative measurements give results that are definite, usually as numbers and units. • Example:
![Accuracy and Precision Measurements work best when they are accurate and precise Accuracy and Precision • Measurements work best when they are accurate and precise –](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-2.jpg)
Accuracy and Precision • Measurements work best when they are accurate and precise – Accuracy is a measure of how close a measurement comes to the actual or true value of whatever is measured. • To evaluate the accuracy of a measurement, it must be compared to the correct value. – Precision is a measure of how close a series of measurements are to one another. • The precision of a measurement depends on more than one measurement.
![Accuracy and Precision Accuracy and Precision](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-3.jpg)
Accuracy and Precision
![Accuracy and Precision Accuracy and Precision](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-4.jpg)
Accuracy and Precision
![Accuracy and Precision In this picture all of the darts land on the Accuracy and Precision • In this picture, all of the darts land on the](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-5.jpg)
Accuracy and Precision • In this picture, all of the darts land on the bullseye which illustrates good precision and accuracy. • In this picture, all of the darts land near each other, but away from the bulls-eye which illustrates good precision, but poor accuracy.
![Accuracy and Precision Here the darts are not close to each other but Accuracy and Precision • Here the darts are not close to each other, but](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-6.jpg)
Accuracy and Precision • Here the darts are not close to each other, but are close to the bulls-eye indicating poor precision, but good accuracy. • Finally, the darts are not close to each other or near the bulls-eye indicating both poor accuracy and poor precision.
![Accuracy and Precision Sometimes there is a difference between the accepted value and Accuracy and Precision • Sometimes there is a difference between the accepted value and](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-7.jpg)
Accuracy and Precision • Sometimes there is a difference between the accepted value and the experimental value. • This difference is known as error. Error = accepted value – experimental value – Error can be positive or negative depending on whether the experimental value is greater than or less than the accepted value.
![Accuracy and Precision Often it is useful to calculate relative error or percent Accuracy and Precision • Often it is useful to calculate relative error, or percent](https://slidetodoc.com/presentation_image_h2/7f4bead7c289e9f0448bb50e10dcc93a/image-8.jpg)
Accuracy and Precision • Often it is useful to calculate relative error, or percent error x 100% Percent error = accepted value – The percent error will always be a positive value.